GPU to pair with my Ryzen 5 1600?

I am looking for a GPU to pair with my Ryzen 5 1600 to play games at 1440p. My current specs are

Asus TUF B450-Plus Gaming Motherboard
16 GB of Corsair 2666 MHz RAM running at 2400 MHz because system won’t boot at a higher clock
Ryzen 5 1600 at stock clock
XFX RX 580 GTS

I really don’t want to upgrade my CPU yet because I don’t want to reinstall windows.

What’s your power supply wattage and what’s the most intensive game you’re looking to play?

My PSU is the EVGA 850 GQ 80 Plus Gold. I went ahead and got the MSI Geforce RTX 2060 Super Gaming X. My RX 580 was overheating while playing The Witcher 3 no matter what even after downclocking. I never overclocked it either but every 30 minutes or less the screen would go black but come right back after 3-4 seconds intermittently. After doing research it seems this is a common problem with the RX 580. No matter what I tried I couldn’t fix the problem other than getting a new GPU.

Now does anyone know why I can’t get my RAM to run at 2666 MHz? This is the RAM I have

I do not know anything about overclocking RAM. I simply just select a profile in the BIOS or UEFI whatever you want to call it these days. It will not boot with anything higher than 2400 MHz :frowning: